Schedule of Available for Sale Marketable Securities (Detail) - USD ($) $ in Thousands	Jul. 02, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	$ 1,019,284	$ 1,304,711
Available-for-sale marketable securities, Unrealized Gain	5,167	2,977
Available-for-sale marketable securities, Unrealized (Loss)	(2,612)	(2,821)
Available-for-sale marketable securities, Fair Market Value	1,021,839	1,304,867
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	928,688	732,979
U.S. Treasury Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	814,699	901,975
Available-for-sale marketable securities, Unrealized Gain	69	97
Available-for-sale marketable securities, Unrealized (Loss)	(2,291)	(2,034)
Available-for-sale marketable securities, Fair Market Value	812,477	900,038
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	808,057	572,284
Corporate Debt Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	62,766	99,708
Available-for-sale marketable securities, Unrealized Gain	1,954	1,065
Available-for-sale marketable securities, Unrealized (Loss)	(267)	(620)
Available-for-sale marketable securities, Fair Market Value	64,453	100,153
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	33,059	53,642
U.S. Government Agency Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	28,135	42,026
Available-for-sale marketable securities, Unrealized Gain	7	7
Available-for-sale marketable securities, Unrealized (Loss)	(21)	(19)
Available-for-sale marketable securities, Fair Market Value	28,121	42,014
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	20,800	13,461
Certificates of Deposit and Time Deposits
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	22,245	82,080
Available-for-sale marketable securities, Unrealized Gain	8	54
Available-for-sale marketable securities, Unrealized (Loss)		(1)
Available-for-sale marketable securities, Fair Market Value	22,253	82,133
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses		7,760
Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	73,291	161,672
Available-for-sale marketable securities, Unrealized Gain		24
Available-for-sale marketable securities, Unrealized (Loss)	(16)	(66)
Available-for-sale marketable securities, Fair Market Value	73,275	161,630
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	65,401	84,034
Equity And Debt Mutual Funds
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	17,570	16,505
Available-for-sale marketable securities, Unrealized Gain	3,122	1,724
Available-for-sale marketable securities, Unrealized (Loss)	(17)	(58)
Available-for-sale marketable securities, Fair Market Value	20,675	18,171
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses	1,371	1,661
Non-U.S. Government Securities
Schedule of Available-for-sale Securities
Available-for-sale marketable securities, Cost	578	745
Available-for-sale marketable securities, Unrealized Gain	7	6
Available-for-sale marketable securities, Unrealized (Loss)		(23)
Available-for-sale marketable securities, Fair Market Value	$ 585	728
Available-for-sale marketable securities, Fair Market Value of Investments with Unrealized Losses		$ 137

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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